Considerable efforts and resources have been channeled into drug research and rehabilitation programs throughout the United States. Most of these efforts, however, are still focused upon individuals, as if they were devoid of continuing relationships, such as marriages or other ongoing, living-together relationships, which can have positive as well as negative impacts on drug rehabilitation efforts. The basic aim of this continuing study is the systematic investigation of couple interaction among persons who have life styles which vary in the degrees to which they are opiate-involved, i.e., 1) current opiate users; 2) those in methadone treatment programs; 3) detoxified, opiate-free persons; and 4) "normal" controls who are similar except that they have never been opiate-addicted. The primary focus of this research will continue to be directed to the identification of those dimensions of couple interaction which distinguish the relationships of couples in the four criterion groups. Pilot study data from the first year of this project suggest that there is support for the general hypothesis that the greater the opiate involvement, the poorer the quality of couples' interaction and relationships. The initial data from 25 opiate-involved couples have already suggested information which could be used by family therapists to increase addicts' facilitative behaviors and decrease their dysfunctional behaviors. More information may not only improve the quality of addicts' relationships, but reinforce drug rehabilitation efforts as well. The basic methodology involves the use of observation and behavioral assessment of couples in their own home as well as in a home-simulated laboratory, in addition to a number of self-reports in interviews and questionnaires.